I am having this issue with 11.10 . Ubiquity doesn't detect the existing windows 7 partition and when I choose to manually partition the disk, I can't see any partition there.
When I log into the live system and open Disk Utility, It shows my HDD partitions fine but Ubiquity for some reason is unable to detect them.
Can't install 11.10 'cause of this issue 🙁 I tried installing 12.04 Alpha 1 and the issue still persists.
There's already a bug [Link: http://pad.lv/798285 ] report regarding the issue but it seems that the report has gone unnoticed.
Is there any way I can still be able to install Ubuntu on this system.
EDIT:
Here's the output of sudo fdisk -lu
ubuntu@ubuntu:~$ sudo fdisk -lu
WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.
Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x66daaff3
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 212994047 106496000 7 HPFS/NTFS/exFAT
Disk /dev/sdb: 988 MB, 988282880 bytes
31 heads, 61 sectors/track, 1020 cylinders, total 1930240 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000d3ee9
Device Boot Start End Blocks Id System
/dev/sdb1 * 61 1928819 964379+ c W95 FAT32 (LBA)
Screenshot: Disk Utility can detect the NTFS partition but ubiquity doesn't.
Best Answer
It looks like this disk used to use GPT, but then you used a non GPT aware tool to redo the msdos partition table, so now the system isn't sure which partition table it should be using. You will need to remove the broken GPT to properly go back to using the msdos table, which you can do with the
gdisk
utility.